1. Field
The system lies in the field of package and article carriers, and more specifically, devices or systems for carrying articles by an animate bearer, and systems for carrying articles at the front torso of a human being.
2. Discussion of the Background
Since time immemorial, human beings have used systems to assist them in carrying articles. People have used, for example, garment pockets, hand-carried containers, shoulder slings, backpacks, and frontpacks.
For anatomical reasons it is usually more efficient to carry an extremely heavy load on the back of the torso, for example, using a backpack. However, a frontpack—i.e., a system for carrying articles at the front of the torso—offers at least two load-carrying advantages.
First, a frontpack enables the user to conveniently see and reach the carried articles without removing the carrier system from the body. This is especially practical for retrieving and replacing frequently used articles such as cameras, binoculars, water bottles, hats, gloves, and the like.
Second; when used in conjunction with a backpack, a frontpack counterbalances certain masses and forces of the backpack upon the user's body, making the total load feel lighter and more comfortable to carry. Redistributing a portion of the total weight of the carried articles from the back of the body to the front of the body shifts the center of gravity of the total load forward, toward the natural center of gravity of the user's body, allowing the user to stand and move in a more natural upright position. If the frontpack has a load-bearing frame that transmits the weight of the front-carried load to the frontal area of the user's hips, the downward force on the front of the pelvic bones will counterbalance the downward force of the backpack on the back of the pelvic bones, bringing the pelvis into a more natural alignment with less strain on low back muscles. A well-designed frontpack frame will also generate forward horizontal forces upon the upper shoulder straps of the backpack to which the frontpack is attached, which will counteract the rearward horizontal forces upon the upper shoulder straps generated by the backpack and its contents. These biomechanical advantages of a frontpack combine to give the user improved comfort, balance, and physical capability while carrying a heavy load.
During the past several decades, the art of backpack design has advanced considerably. Early backpacks consisted of little more than flaccid bags suspended from the user's shoulders by simple straps. Today, state-of-the-art backpacks utilize rigid frames to transfer the weight of the load to the user's hips, which is the optimal anatomical location for a person to bear a heavy load. Modern suspension systems are adjustable and utilize padded and anatomically shaped shoulder straps and hip belts for improved fit, comfort, freedom of movement, and load stability. These advancements allow the users of modem backpacks to carry heavier loads and to engage in more physically demanding activities than was possible at any time in the past.
Devices for carrying articles at the front of the human torso have not seen similar advancements in design or performance. In the prior art, no frontpack system is known that has offered satisfactory weight transfer to the hips, adjustability, comfort, freedom of movement, and load stability.
The simplest prior art frontpack designs involve a container suspended from a single strap deployed over the user's neck or a single shoulder. A supplemental strap is sometimes deployed circumferentially around the user's torso to limit the bouncing and swaying of the front-carried load. Frontpacks of this type suffer from a fundamental shortcoming in the relatively limited capacity of the human neck and shoulders to carry a heavy load. Even a comparatively light item such as a camera or pair of binoculars becomes uncomfortable when suspended from the neck or a single shoulder for a sustained period of time.
Another form of unsophisticated frontpack involves the use of pockets sewn into the front of a garment. Examples of this approach are found in a traditional fisherman's vest and, for example, in the combination backpack/vest taught by Wooley, U.S. Pat. No. 6,397,392, in which a vest has front and rear pockets. This approach affords slightly greater frontal load-carrying capacity, because the weight of the load is distributed over both of the user's shoulders, rather than over the neck or only one shoulder. This approach is still quite limiting, however, due to the lack of weight transfer to the user's hips and practical constraints on the size and shape of front-carry garment pockets.
Another form of unsophisticated frontpack entails, in essence, modifying a backpack so that it can be worn on the front of the body. With minor alterations to the straps and pack bag, a simple frameless backpack design can be adapted to front-carry duty. Examples of this approach are found in a variety of prior art soft frontpacks for carrying infants and small pets. These systems are simple, inexpensive, and adequate for casual and lightweight usage, but the lack of weight transfer to the hips and effective load control capabilities render them unsuitable for sustained or demanding front-carry activities.
Yet another frontpack design approach is exemplified by Radar, U.S. Pat. No. 5,586,703, Baclawski, U.S. Pat. No. 5,634,579, and Jackson, U.S. Pat. No. 6,402,003, each of which teaches frontal pockets suspended from the shoulder straps of a backpack. Because these systems cooperate with a modern backpack, they offer improved comfort and load-carrying capacity due to the exploitation of modern backpack shoulder strap design and the ability to achieve improved back-to-front weight distribution. However, none of these systems achieves the transfer of front-carried weight directly to the user's hips, where the load can be carried most comfortably and efficiently; nor do these systems provide adequate load control capabilities.
Several prior art frontpack systems have made advances in transferring the weight of the front-carried load downward to the hips of the user by utilizing a rigid framework to support the front-carried load. One category of such systems utilizes a rigid backpack frame with sections that extend forward from the backpack to the front of the user's body. The weight of articles carried on the forward-extending frame sections is mechanically transferred to the backpack and thus is carried on the back of the user's body. This approach is seen, for example, in Turchen, U.S. Pat. No. 4,037,763, and Zufich, U.S. Pat. No. 4,114,788. These systems achieve some success in mechanically transferring a portion of the weight of the front-carried load to the hips of the user, via the backpack frame. However, because there is no support for the front-carried load at the front of the user's body, these systems lack effective load control capability and do not achieve any balancing of the downward forces at the back and front of the user's pelvic bones.
The foregoing deficiencies and limitations are avoided to some degree in the class of front-carry systems that utilizes a rigid framework to transfer the weight of the front-carried load, or at least a portion of it, directly downward to the frontal area of a hip belt worn by the user. This design approach is exemplified in Stanford, U.S. Pat. No. 4,480,775, Bell, U.S. Pat. No. 4,892,240, Easter, U.S. Pat. No. 6,336,576, and Tate, U.S. Pat. No. 5,497,922. While these systems represent advancements in the state of the art of frontpacks, each system has shortcomings.
Bell, U.S. Pat. No. 4,892,240, teaches an “exoskeletal carriage” that is essentially a rigid garment to which pockets or other carrying mechanisms may be attached. Such a system provides no means of cooperation with a separate backpack. It is incapable of being adjusted to accommodate the different body shapes and sizes of different users. To achieve adequate control of the front-carried load against bouncing and swaying, the Bell “exoskeleton” must be strapped snugly to the torso. Such snug strapping is uncomfortable and inhibits ventilation of perspiration between the “exoskeleton” and the body. In addition, such snug strapping causes a portion of the weight of the load to be carried upon the upper regions of the torso, and it is therefore counterproductive to full weight transfer to the hips. Perhaps most detrimentally, the rigid “exoskeleton” severely restricts the normal movements of the user's torso. As a person moves through a typical range of motion from reaching up high to bending over forward—or bending from side to side—the person's torso bends and the distance between the front of the hips and the front of the shoulders varies by several inches, sometimes more on one side than on the other. Additionally, when a person's upper torso twists or rotates axially toward the left or the right in relation to the lower torso, the distances between the shoulders and the frontal areas of the hips are changed, sometimes more on one side than the other. Strapping a rigid front-carry plate onto the front torso of the user impedes this range of motion.
The frontpack taught by Stanford, U.S. Pat. No. 4,480,775, utilizes a full external frame, reminiscent of a modern external backpack frame. Stanford's frontal frame is secured to the user's torso by a plurality of straps. With the Stanford system, as with an external frame backpack, the rigid frame theoretically allows for the transfer of a significant portion of the weight of the carried load downward to a hip belt encircling the hips of the user. As taught by Stanford, however, bouncing and swaying of the front-carried load can be controlled only by strapping the framework tightly against the user's torso. Such tight strapping is counterproductive to the transfer of weight to the user's hips. In addition, such tight strapping restricts freedom of movement and diminishes the user's comfort and ventilation. Furthermore, the Stanford frame is not adjustable to accommodate users of different sizes and shapes, and the Stanford body harness is cumbersome and provides no mechanism for cooperation with a separate backpack.
The frontpack described in Easter, U.S. Pat. No. 6,336,576, utilizes a pair of external rigid frame sections to transfer the weight of the frontpack and the front-carried load to the front of a prior art backpack hip belt. Although this design in theory allows reasonable freedom of movement and weight transfer to the front of the hips, the Easter system, like those of Stanford and Bell, lacks effective load control capabilities. Bouncing is inadequately controlled due to the lack of a positive connection between the frontpack and the backpack hip belt. Swaying is ineffectively controlled because the upper region of the frontpack is attached to the sternum strap of the backpack, which is not a stable anchor point. Modest load control can be achieved in the Easter system only by excessively tightening the shoulder straps and the sternum strap, which will inescapably decrease freedom of movement, decrease comfort, and decrease weight transfer to the hip belt. Finally, while the Easter system is especially well-suited to carrying equipment used in the pursuit of wildlife, this specialization renders the system ill-adapted to use for other front-carrying activities.
Tate, U.S. Pat. No. 5,497,922, teaches the use of “counter balance pockets” with rigid internal frame sections to transfer a majority of the weight of the pockets and their contents to the frontal area of a backpack hip belt. Tate has commercially produced this frontpack system and a line of cooperating backpacks sold under the trademark “Aarn Bodypacks.” Although Tate's frontpack design in theory provides significant weight transfer to the front of the user's hips, bouncing and swaying in the Tate system can be adequately controlled only by tightening various straps embodied within the system, which inescapably decreases freedom of movement, comfort, and weight transfer to the hip belt. The counterbalance pockets in the Tate system are attached to the shoulder straps of a backpack by a common plastic loop encircling a vertical webbing strap on the backpack shoulder strap. This attachment system affords a limited range of motion for the user's upper torso and limits the ability of the Tate system to cooperate with a wide range of backpacks. Finally, the pockets taught by Tate inherently constrain the size and shape of articles that may be carried. For example, Tate's pockets cannot effectively carry a rifle, a pair of skis, a camera tripod, or an infant.
LuxuryLite (luxurylite.com) offers for sale a “front hydration pack” comprising a clear plastic envelope that hangs by straps from top of a backpack frame and tucks into the front of the hip belt of the backpack. According to the manufacturer, three 24-ounce plastic water bottles bought at a grocery store can be carried inside the frontpack to give it rigidity so the weight of the frontpack is transmitted downward to the user's hips. The LuxuryLite system does not have a rigid integral frame; it does not robustly connect to the hip belt of a backpack; it provides no means of connection to the shoulder straps of a backpack; and it provides no rigid structure in the upper region of the frontpack to prevent the upper region from swaying and rocking during real-world activities like hiking over rough terrain.
It can therefore be seen that there is a need for a frontpack system that will:
(a) transfer a substantial portion of the weight of the frontpack and the front-carried load vertically downward to the frontal area of the user's hips;
(b) accommodate the natural range of motion of the user's torso during diverse activities by automatically changing the length or configuration of the frontpack system to meet and match the dynamic changes in the position of the user's torso;
(c) control the frontpack and any front-carried load against up-and-down bouncing, side-to-side swaying, and front-to-back rocking when the user is moving or traveling;
(d) position and maintain the frontpack and any front-carried load at an optimal distance from the front torso of the user to maximize user comfort;
(e) adjust in multiple dimensions to properly fit users of different sizes and shapes;
(f) carry and secure a wide range of sizes, shapes, and weights of articles; and
(g) cooperate with a prior art or future backpack, or with a dedicated front-carry harness, or with any other suitable harness worn by the user.